Users may interface with computing systems using a variety of input mechanisms. For example, eye gaze tracking may be utilized to interact with a graphical user interface, wherein a determined location at which a user's gaze intersects the graphical user interface may be used as a positional signal for interactions with the user interface. Gaze tracking techniques may employ one more light sources to project light onto an eye, and one or more cameras to capture images of glints of the projected light as reflected from the eye. The locations of the glints and/or the pupil in the images may be utilized to determine a pupil position indicating a gaze direction.